The ttree script is used to process entire directory trees containing template files. The resulting output from processing each file is then written to a corresponding file in a destination directory. The script compares the modification times of source and destination files (where they already exist) and processes only those files that have been modified. In other words, it is the equivalent of 'make' for the Template Toolkit.

It supports a number of options which can be used to configure behaviour, define locations and set Template Toolkit options. The script first reads the .ttreerc configuration file in the HOME directory, or an alternative file specified in the TTREERC environment variable. Then, it processes any command line arguments, including any additional configuration files specified via the -f (file) option.

The purpose of this file is to set any global configuration options that you want applied every time ttree is run. For example, you can use the ignore and copy option to provide regular expressions that specify which files should be ignored and which should be copied rather than being processed as templates. You may also want to set flags like verbose and recurse according to your preference.

In most cases, you'll want to create a different ttree configuration file for each project you're working on. The cfg option allows you to specify a directory where ttree can find further configuration files.

cfg = /home/abw/.ttree

The -f command line option can be used to specify which configuration file should be used. You can specify a filename using an absolute or relative path:

If the configuration file does not begin with / or . or something that looks like a MS-DOS absolute path (e.g. C:\\etc\\ttree.cfg) then ttree will look for it in the directory specified by the cfg option.

$ ttree -f test1 # /home/abw/.ttree/test1

The cfg option can only be used in the .ttreerc file. All the other options can be used in the .ttreerc or any other ttree configuration file. They can all also be specified as command line options.

Remember that .ttreerc is always processed before any configuration file specified with the -f option. Certain options like lib can be used any number of times and accumulate their values.

For example, consider the following configuration files:

/home/abw/.ttreerc:

cfg = /home/abw/.ttree
lib = /usr/local/tt2/templates

/home/abw/.ttree/myconfig:

lib = /home/abw/web/example/templates/lib

When ttree is invoked as follows:

$ ttree -f myconfig

the lib option will be set to the following directories:

/usr/local/tt2/templates
/home/abw/web/example/templates/lib

Any templates located under /usr/local/tt2/templates will be used in preference to those located under /home/abw/web/example/templates/lib. This may be what you want, but then again, it might not. For this reason, it is good practice to keep the .ttreerc as simple as possible and use different configuration files for each ttree project.

The src option is used to define the directory containing the source templates to be processed. It can be provided as a command line option or in a configuration file as shown here:

src = /home/abw/web/example/templates/src

Each template in this directory typically corresponds to a single web page or other document.

The dest option is used to specify the destination directory for the generated output.

dest = /home/abw/web/example/html

The lib option is used to define one or more directories containing additional library templates. These templates are not documents in their own right and typically comprise of smaller, modular components like headers, footers and menus that are incorporated into pages templates.

The lib option can be used repeatedly to add further directories to the search path.

A list of templates can be passed to ttree as command line arguments.

$ ttree foo.html bar.html

It looks for these templates in the src directory and processes them through the Template Toolkit, using any additional template components from the lib directories. The generated output is then written to the corresponding file in the dest directory.

If ttree is invoked without explicitly specifying any templates to be processed then it will process every file in the src directory. If the -r (recurse) option is set then it will additionally iterate down through sub-directories and process and other template files it finds therein.

$ ttree -r

If a template has been processed previously, ttree will compare the modification times of the source and destination files. If the source template (or one it is dependant on) has not been modified more recently than the generated output file then ttree will not process it. The -a (all) option can be used to force ttree to process all files regardless of modification time.

$ tree -a

Any templates explicitly named as command line argument are always processed and the modification time checking is bypassed.

The ignore, copy and accept options are used to specify Perl regexen to filter file names. Files that match any of the ignore options will not be processed. Remaining files that match any of the copy regexen will be copied to the destination directory. Remaining files that then match any of the accept criteria are then processed via the Template Toolkit. If no accept parameter is specified then all files will be accepted for processing if not already copied or ignored.

The suffix option is used to define mappings between the file extensions for source templates and the generated output files. The following example specifies that source templates with a .tt2 suffix should be output as .html files:

suffix tt2=html

Or on the command line,

--suffix tt2=html

You can provide any number of different suffix mappings by repeating this option.

The depend and depend_file options allow you to specify how any given template file depends on another file or group of files. The depend option is used to express a single dependency.

$ ttree --depend foo=bar,baz

This command line example shows the --depend option being used to specify that the foo file is dependant on the bar and baz templates. This option can be used many time on the command line:

$ ttree --depend foo=bar,baz --depend crash=bang,wallop

or in a configuration file:

depend foo=bar,baz
depend crash=bang,wallop

The file appearing on the left of the = is specified relative to the src or lib directories. The file(s) appearing on the right can be specified relative to any of these directories or as absolute file paths.

For example:

$ ttree --depend foo=bar,/tmp/baz

To define a dependency that applies to all files, use * on the left of the =.

$ ttree --depend *=header,footer

or in a configuration file:

depend *=header,footer

Any templates that are defined in the pre_process, post_process, process or wrapper options will automatically be added to the list of global dependencies that apply to all templates.

The depend_file option can be used to specify a file that contains dependency information.

Lines beginning with the # character are comments and are ignored. Blank lines are also ignored. All other lines should provide a filename followed by a colon and then a list of dependant files separated by whitespace, commas or both. Whitespace around the colon is also optional. Lines ending in the \ character are continued onto the following line.

Files that contain spaces can be quoted. That is only necessary for files after the colon (':'). The file before the colon may be quoted if it contains a colon.

As with the command line options, the * character can be used as a wildcard to specify a dependency for all templates.